| Big Spring to Olympia Heights (Florida) | 1,351.89 mi (2,175.65 km) |
| Big Spring to Omaha (Nebraska) | 691.72 mi (1,113.21 km) |
| Big Spring to On Top of the World Designated Place (Florida) | 1,159.30 mi (1,865.71 km) |
| Big Spring to Onalaska (Wisconsin) | 978.13 mi (1,574.15 km) |
| Big Spring to Oneida (New York) | 1,589.26 mi (2,557.66 km) |
| Big Spring to Oneonta (New York) | 1,604.33 mi (2,581.93 km) |
| Big Spring to Ontario (California) | 940.25 mi (1,513.19 km) |
| Big Spring to Ontario (Oregon) | 1,167.78 mi (1,879.36 km) |
| Big Spring to Opa-locka (Florida) | 1,351.68 mi (2,175.32 km) |
| Big Spring to Opelika (Alabama) | 938.44 mi (1,510.27 km) |
| Big Spring to Opelousas (Louisiana) | 566.66 mi (911.96 km) |
| Big Spring to Orange (California) | 951.86 mi (1,531.88 km) |
| Big Spring to Orange (Texas) | 479.01 mi (770.90 km) |
| Big Spring to Orange City (Florida) | 1,220.57 mi (1,964.32 km) |
| Big Spring to Orangeburg (South Carolina) | 1,197.42 mi (1,927.06 km) |
